This invention relates to food products and more particularly to food products of an amylaceous character containing heat stable .alpha.-amylase which is added in amounts sufficient to maintain or improve the soft texture after a heat treatment.
While it is well recognized that many features contribute to the taste of a food, it is equally well recognized that an important taste feature of a food is its texture, or, the relative softness of the food. A food that feels hard or conversely, extremely soft or mushy may not be acceptable, the desired texture lying generally somewhere in the intermediate range. Foods such as meat or meat substitutes are usually expected to be relatively soft. Some products though initially of a soft texture, such as bread, are known to stale and become hard upon storage. No imagination is needed to realize that with a wide variety of foods, texture or, retaining a soft texture, can be a large problem.
Even though it is possible to manufacture a food product having initially the desired soft texture, staling and the like are factors encountered on storage which can have an adverse effect on texture.
Because such hardness and change in texture is inherently undesirable in most food products, it thus becomes clearly desirable to prevent this change in texture or reduce the texture deterioration in a stored food.
Procedures are known in the prior art for achieving a food having a soft texture by addition of such ingredients as humectants. In some cases, a food which is manufactured with a soft texture has such a low amount of texture deterioration that storage is highly feasible for that food without a substantial loss in texture. Even in these cases, there is some loss of texture which can become detrimental if the storage is overly extended. The components generally used to achieve the desired texture are costly and can have a somewhat adverse effect on palatability.
Besides the use of humectants as taught in U.S. Pat. No. 3,202,514 to Burgess, another way to achieve and maintain a soft texture is through the use of certain emulsifiers which tend to complex with the starch, thereby retarding starch degradation. However emulsifiers only slow down the rate of staling, and do not completely inhibit it.
It has been known in the past to add an amylase enzyme to bakery products such as breads, to achieve a softening of the bread texture. However, in the baking process, the bread dough is cooked at a sufficiently high temperature for a sufficiently long time to assure inactivation of the enzyme during baking. Thus no texturization of the bread can occur after baking, and the bread also will become hard or stale with time.